backlight: Remove bogus SYSFS dependency

Remove a bogus SYSFS dependency from the backlight class

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index cd2ef0a..f8bc43c 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -4,9 +4,7 @@
 
 menu "Graphics support"
 
-if SYSFS
-	source "drivers/video/backlight/Kconfig"
-endif
+source "drivers/video/backlight/Kconfig"
 
 config FB
 	tristate "Support for frame buffer devices"